Vol.:(0123456789) 1 3 Molecular Biology Reports https://doi.org/10.1007/s11033-019-05043-8 ORIGINAL ARTICLE Hempseed protein hydrolysates’ effects on the proliferation and induced oxidative stress in normal and cancer cell lines Marijan Logarušić 1  · Igor Slivac 1  · Kristina Radošević 1  · Martina Bagović 1  · Ivana Radojčić Redovniković 1  · Višnja Gaurina Srček 1 Received: 5 April 2019 / Accepted: 21 August 2019 © Springer Nature B.V. 2019 Abstract Food proteins from different sources can provide beneficial effects on human health by releasing the bioactive peptides that are integral part of their native structure. In this study, we tested the biological potential of hempseed protein hydrolysates (HPHs) obtained from hempseed cake protein isolate. The HPHs were prepared by enzyme hydrolysis using three different proteases of microbial origin: Alcalase®, Neutrase® and Protamex®. The antioxidant activity of the obtained hydrolysates was determined by oxygen radical absorbance capacity (ORAC) assay, while the proliferative effects on normal (HaCaT) and cancer (HeLa) cells were determined by the CellTiter 96 ® AQ ueous One Solution Reagent (MTS) assay. HPHs showed dose- dependent antiproliferative effects on HeLa cells and stimulatory effects on the proliferation of HaCaT cells. HPH obtained by Neutrase ® (HPH-N) showed the highest antioxidant activity expressed as an ORAC value. The protective effect of HPH-N on H 2 O 2 -induced oxidative stress in normal and cancer cells was evaluated and 1 mg/mL of HPH-N significantly reduced the formation of intracellular reactive oxygen species (ROS) in both cell lines. The obtained results indicate the benefits of HPHs as potential natural antioxidants for the food industry and contribute to the growing trend of utilizing hempseed by-products. Keywords Antioxidant activity · Antiproliferative effects · Hempseed protein hydrolysates · ORAC value Introduction Oil cakes, which are by-products obtained after oil extrac- tion from certain industrial plant seeds, are a potential source for many valuable components like plant proteins, fibres and phenolic compounds. They have been recognized as an interesting by-product suitable for valorisation as either human food or animal feed [1]. In recent years, many research groups have focused on the production of pep- tides/hydrolysates with a potential application for the food and nutraceutical industries [2]. Food proteins can provide beneficial impacts to human health by releasing the bioac- tive peptides that are encrypted in their native structures. It has been reported that protein hydrolysates or bioactive peptides derived from food proteins perform a wide range of bioactivities including immunomodulatory, anticancer, antihypertensive, antioxidant, osteoprotective and antimi- crobial effects [2, 3]. Industrial hemp (Cannabis sativa L.) seed is by-product obtained after the utilization of plant fibres and is mainly used for oil extraction. Hempseed oil contains over 90% pol- yunsaturated fatty acids [4] and is utilized as a component for cosmetic products or as a functional food [5]. Hempseed cake, a by-product of oil extraction, contains 20–25% pro- teins [4] and its amino acid profile showed similar or even higher levels of essential amino acids (except for lysine) compared to soy proteins [6]. Furthermore, hempseed pro- tein hydrolysates (HPHs) obtained by different proteases had antioxidant properties [3, 7, 8] that were dependent on the enzyme type and the hydrolysis conditions. Recent studies have reported the protective effects of HPHs on induced oxi- dative stress in PC12 cells [5] and HepG2 cells [8]. However, more studies are needed to investigate the biological effects of HPHs in order to transform protein rich by-products into valuable products. The aim of this study was to prepare HPHs from hemp- seed protein isolate (HPI) using three different proteases, Alcalase®, Neutrase® and Protamex®, and to evaluate their * Višnja Gaurina Srček vgaurinasrcek@pbf.hr 1 Laboratory for Cell Technology and Biotransformation, Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia